This invention relates to a fixed telephone set such as an IP (Internet Protocol) telephone set and, in particular, relates to a button telephone set.
Generally, this type of fixed telephone set, particularly, a button fixed telephone set, comprises a telephone body, a handset, and a cradle. The telephone body has dial keys, one-touch keys, a hold key, and so on. The cradle supports the handset. In such a button fixed telephone set, the cradle is provided with, in addition to a support portion for supporting the handset, a loudspeaker, a hook switch, and so on.
Japanese Unexamined Patent Application Publication (JP-A) No. Hei 07-123139 discloses a fixed telephone set that allows achieving a hold function by hanging a handset on a cradle, i.e. without providing a hold key on a telephone body (related art 1).
Japanese Unexamined Patent Application Publication (JP-A) No. 2005-12364 discloses a fixed telephone set that allows making a call by removing a handset with a microphone from a cradle (related art 2). In the related art 2, it is possible to suspend a telephone conversation with a communication partner by stopping sending audio signals, output from the microphone, to the communication partner depending on whether or not a user is close to the handset. As a result, it is possible to shield a conversation that the user does not want the communication partner to hear.
In the related art 1, the telephone body having dial keys and so on and the cradle for supporting the handset are integrated with each other. Further, in the related art 2, a telephone body is integrally incorporated in the cradle.
In the case of a fixed telephone set in which a telephone body and a cradle are integrated with each other like the related arts 1 and 2, since a loudspeaker is incorporated in the cradle, there have been instances where while making a hands-free telephone conversation, not requiring use of a handset, through a microphone and a loudspeaker of the telephone body, howling occurs due to these microphone and loudspeakers to make it difficult to hear the conversation. Further, there have also been instances where heat is generated from semiconductors and so on mounted in the telephone body during a call and this heat is transferred to the handset placed on the cradle, thus giving an unpleasant feeling to a user when using the handset due to its temperature rise. That is, in the conventional fixed telephone set, no consideration is given to the problem of howling or the problem of temperature rise of the handset that occurs when the cradle and the telephone body are integrated with each other.
Further, in the manufacture of fixed telephone sets of types in which a telephone body and a cradle are integrated with each other, it is necessary to prepare molds and associated parts corresponding to all the types of fixed telephone sets, respectively. Therefore, there is a drawback that when changing the type, the function, or the like, it is necessary to newly prepare a mold and associated parts for use in manufacturing an intended fixed telephone set and thus it is not possible to flexibly cope with the change in type or the like. Further, it is also not possible to change the external appearance of a fixed telephone set according to the taste of a user.